1. Field of the Invention
The present invention relates to a handpiece for dental medical treatment used for removing and cutting treatments of the affected tooth part.
2. Description of the Prior Art
In a conventional handpiece of this kind, an air turbine is encased in a head portion at the extreme end of a handpiece body and a spray port for a cooling water is provided. A cutting tool is inserted into a tubular rotary shaft of the air turbine. The air turbine is driven by compressed air which flows through air supply and discharge flowpassages within the handpiece body whereby the cutting tool rotates at high speed to remove and cut the affected tooth part.
Incidentally, the greatest problem in the recent dental medical field is to prevent the secondary infection of AIDS (Acquired Immune Deficiency Syndrome), hepatitis, etc. The conventional handpiece constructed as described above can be mentioned as one of those which most likely comprises an infectious medium in the actual medical site.
That is, in order to prevent infection of the virus infectious symptoms, high temperature sterilization by boiling is most effective. However, in the conventional handpiece, the air turbine encased in the head portion thereof is not formed so as to withstand the high temperature sterilization by boiling. It is contemplated in order to overcome this problem that the high temperature durability of the air turbine is improved or a sterilization method by a sterilization gas is used. In the case of employing these means, however, there possibly brings forth an increase of manufacturing cost of a handpiece or expenses for sterilization, and accordingly, high cost of medical expenses and a substantial increase of a burden by patients.
The present invention has been accomplished in view of the circumstances noted above with respect to prior art. It is a primary object of the present invention to employ a sterilization method by boiling which is most effective and inexpensive for prevention of infection and to maintain an aseptic condition of the whole hand-piece without requiring of improving high temperature durability of an air turbine. A second object of the invention is to realize the aforesaid primary object at extremely low cost.